1. Field of the Invention
The present invention relates to a semiconductor device.
2. Description of the Related Art
A Reverse Conducting—Insulated Gate Bipolar Transistor (an RC-IGBT), which includes a diode and an IGBT, is disclosed in FIG. 2 of U.S. 2010/276727.
The RC-IGBT includes a semiconductor layer. A p type channel region is formed at a surface layer portion of the semiconductor layer. An n type emitter region is formed at a surface layer portion of the channel region. An n type drift region is formed so as to be electrically connected to the channel region at a rear surface side of the semiconductor layer with respect to the channel region of the semiconductor layer.
At a surface layer portion of the rear surface of the semiconductor layer, a p type collector region is formed so as to be electrically connected to the drift region. A plurality of n type cathode regions is formed so as to be electrically connected to the drift region at surface layer portions of the rear surface of the semiconductor layer. The plurality of n type cathode regions is formed in a matrix pattern at the rear surface of the semiconductor layer.